Method of forming a liquid conveying duct



July 22, 1958 c. 1.. BARRON METHOD OF FORMING A LIQUID CONVEYING DUCT Filed July s, 1956 2 Sheets-Sheet l n PM FE m 5 w t/ Cur ATTORNEYS July 22, 1958 c. L. BARRON METHOD OF FORMING A LIQUID CONVEYING DUCT Filed July 5. 1956 2 Sheets-Sheet 2 4 h warlllim'bylllwkls'm .50 m m a B l w 7 r a C ATTORNEYS.

United States Patent METHOD OF FORMING A LIQUID CONVEYING DUCT Curtis L. Barron, Sacramento, Calif.

Application July 3, 1956, Serial No. 595,667

2 Claims. (Cl. 25-155) This invention relates to a method for making embedded concrete ducts for conveying water or other liquid.

An object of this invention is to provide an improved method for making concrete ducts whereby the duct may in the formative stage thereof, use the ditch or channel in the earth as an outer form, with an inner form of sheet metal material suspended between the vertical walls of the ditch or channel.

Another object of this invention is to provide an improved method for making a concrete duct wherein the initially formed open channel is filled with dirt, and the top or cover is then poured. When the concrete forming the top or cover has set the dirt is removed by the placer method, that is, water is forced under pressure into the duct from one end and the water loosens the dirt which flows as mud from the open end of the duct.

A further object of this invention is to provide a concrete duct with compressible joints between the duct sec tions, the joint elements having anchor rods adapted to be embedded in the abutting ends of the duct sections.

With the foregoing and other objects in View which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts, hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangements of parts without departing from the spirit of the invention as claimed.

Referring to the drawings:

Figure 1 is a vertical section of a form constructed according to an embodiment of this invention to produce an embedded concrete duct.

Fig. 2 is a fragmentary vertical section through the form structure.

Fig. 3 is a fragmentary sectional View taken on line 3-3 of Fig. 1. v

Fig. 4 is a fragmentary vertical section taken on line 4-4 of Fig. 1.

Fig. 5 is a fragmentary sectional view taken on line 5-5 of Fig. 4.

Fig. 6 is a vertical section taken substantially on line 6--6 of Fig. 2.

Fig. 7 is a vertical section taken through the channel chute duct after the initial pouring of the concrete has set with the channel chute member filled with dirt.

Fig. 8 is a vertical section through the completed duct with the bore or channel filled with dirt.

Fig. 9 is a perspective view of one of the gaskets between adjacent duct sections.

Fig. 10 is a fragmentary longitudinal section showing the manner in which the dirt is removed from the completed duct by the placer method.

Referring to the drawings, the numeral designates generally a channel which is formed in the ground. The channel 15 is formed with a horizontal fiat bottom wall 16 and vertical side Walls 17. The channel 15 is formed of a depth substantially greater than the depth of the concrete duct which is to be formed in the channel so that when the duct has been completed this duct may be "ice covered with dirt. The channel 15 forms the outer concrete form and an inner U-shaped form 18 is adapted to be suspended in the channel 15. The U-shaped form member 18 is provided at its upper edges with rolled edges 19 and the form member 18 is suspended within. the channel 15 by means of a plurality of suspension rods 20. The suspension rods 20 have a ball member 21 at the lower ends which engage in a ball socket 22 fixed by fastening means 23 to the inner concave side of the form member 18. The socket member 21 is formed with a slot or opening 24 so that the ball member 21 may be inserted Within the socket member 22 from one side thereof. The suspension rod 20 is threaded as indicated at 25 from a point extending downwardly from the upper end thereof and a pair of nuts 26 and 27 having handles 28 and 29, respectively, are threaded on the threads 25 of rod 20. The rod 20 loosely engages through an apertured ear 38 which projects from a sleeve 31 which is secured in adjusted position on an outer tubular member 32 by means of a set screw 33.v The tubular member 32 forms one part of a pair of longitudinally extensible supporting members with an internal member 34 threaded into the external member 32. The external or tubular member 32 is provided with nuts faces 35 and the internal member 34 is provided with nut faces 36. The outer end of the tubular member 32 is provided with a ground piercing point 37 and the outer end of the inner member 34 is provided with a ground piercing point 38. One end of each form member 18 is provided with a U-shaped coupling member 39 within which the adjacent end of an adjacent form member 18 is adapted to slidably engage. At predetermined points along the length of the channel 15 there is positioned a flexible gasket assembly generally indicated at 40, comprising a compressible expansion joint between sections of the duct, and adapted to be positioned in the ditch prior to the pouring of the concrete. The gasket assembly 40 includes a resilient gasket member 41 having a U-shaped opening 42 of a size similar to the size of the form member 18. The gasket 41 has disposed on opposite faces thereof weights 43 and 44 and the weights 43 and 44 have projecting horizontally and right-angularly therefrom anchoring rods 45 and 46, respectively. These anchoring rods 45 and 46 are adapted to project into the channel 15 so as to become embedded in the concrete, which is poured on the outer side of the form member 18. The form member 18 has chains 47 extending thereacross, which are secured to the upper edges 19 of the form member 18, and the chains 47 include an eye or guide 48 through which the rod 24) loosely engages. These chains 47 provide a means whereby the form member 18 will be held with the straight sides thereof vertical after the manner shown in Fig. 1.

In the first step effecting the supporting of the inner form 18 within the channel 15, the concrete is poured into the channel 15, as shown in Fig. 7, to the level of the upper edge of the form member 18. This concrete forms a Ushaped or channel-shaped duct 49, and at the points where the gasket assemblies 40 are positioned, the upper horizontal portion 50 of each gasket assembly 40 will project above the upper edges of the channel members 49. The height of the projection 50 is such that when the top wall or cover is poured the outer edge of the gasket assembly 40 will be flush with the upper surface of the cover :or top wall. The channel in the channel member 49, after the concrete has become set and form 18 removed, is then filled with dirt, as indicated at 51. The dirt is leveled off at the outer edges of the channel mernber 49. At this time a layer of concrete indicated at 52, is poured on top of the channel member 49 and on top of the dirt 51. The concrete duct is at this time completed, but is filled with the dirt 51. This dirt is then removed by the method as shown in Fig. 10. This method is'similar to the method used in placer mining where a water nozzle 53 is projected into the duct and the water under pressure is directed against the dirt 51 so as to turn this dirt into fluid mud. The mud will then flow out of the duct into a suitable sump which may be provided at one end of the duct.

After the channel member 49 has set with the form 18 still disposed therein, this form 18 may be loosened and partially lifted by turning nut 26 which is the upper nut, so as to pull rod 20 upwardly. In this manner the inner form 18 can be easily loosened and at least partially removed from the set concrete Without injury to the form.

What is claimed is:

1. The method of forming a concrete duct which ineludes forming a channel in the ground with a horizontal bottom and vertical sides, suspending a plurality of channel shaped inner forms in the channel, positioning yieldable gaskets between adjacent forms, each gasket having an opening therein conforming in dimensions to the dimensions of said forms pouring concrete in the channel to the level of the upper edge of the inner form, removing the inner form when the concrete has set, filling the channel shaped duct with dirt to the level of the upper edge thereof, forming a flat top wall on the upper edge of the channel-shaped duct with the top Wall bearing against the dirt in the duct, and removing the dirt by the placer method.

2. The method of forming a concrete duct which includes forming a channel in the ground with a horizontal bottom and vertical sides, suspending a plurality of channel shaped inner forms in the channel, positioning yieldahle gaskets between said forms, each gasket having a central opening therein dimensioned to conform to the di1nensions of said forms pouring concrete in the channel to the level of the upper edge of the inner form, removing the inner form when the concrete has set, filling the channel shaped duct with dirt to the level of the upper edge thereof, forming a fiat top Wall on the upper edge of the channel-shaped duct with the top wall hearing against the dirt in the duct, and discharging water under pressure into the duct to transform the dirt to mud, and Washing the mud from the duct.

References Cited in the file of this patent UNITED STATES PATENTS 1,008,264 Hill Nov. 7, 1911 1,148,246 Marvin July 27, 1915 1,722,038 Daugherty July 23, 1929 1,942,489 Pfefferle Jan. 9, 1934 1,988,900 Heltzel Jan. 22, 1935 2,116,746 \Vells May 10, 1938 2,365,550 Heltzel Dec. 19, 1944 2,575,247 Carter Nov. 13, 195] 2,616,149 Waller Nov. 4, 1952 2,705,360 Leonhardt Apr. 5, 1955 

